The present invention relates generally to apparatus for splicing webs of material together, and more particularly, is directed to a lap splicing apparatus in which the trailing tail end of the splice is always on the same side without using any turret assembly for holding the rolls of web material.
In web transport machines, when a running web nears depletion, it is necessary to splice the trailing end of the running web to the leading end of a new web. There are different types of web splices. Specifically, there is a butt splice in which the ends of the webs are accurately butted together in end to end relationship. The other type of splice is a lap splice in which the leading end of the new web has a piece of double-sided tape and the opposite side of the tape is adhered to the running web at a position offset from the trailing edge thereof. As a result, there is a tail at the trailing end of the running web which overlaps the leading end of the new web.
However, if the two rolls, that is, the roll nearing depletion and the new roll, are fixed in position on spindles, and are then spliced together, the overlying tail of the running web will be on alternate sides of the spliced web during sequential splicing operations. Many end users do not like this arrangement since it may cause problems with the machinery downstream of the splicing assembly. Specifically, the leading edge of the new web on the side opposite from the tail can be caught in a mechanism downstream, which results in the machine being shut down, and the entire line of web material, which can be very long, being rethreaded in the machine. Therefore, many end users require the trailing tail end of the splice to be on the same side at all times.
In order to accomplish this, a turret assembly has generally be provided for holding the two rolls of web material. In such case, the new roll is always indexed to the same position during the splicing operation so that the trailing tail end of the lap splice occurs on the same side at all times. However, this results in additional space being taken up and more complicated machinery.